The present invention relates to a multi-head device for an optical disk capable of writing/reading information on/from the optical disk, and a recording/reproducing system for multiple users utilizing the multi-head device, and more particularly, to a multi-head device for an optical disk and a recording/reproducing system for multiple users utilizing the same in which multiple users may each record or reproduce information with respect to one disk.
As is known in the art, an optical disk drive in which a recordable magneto-optical disk is loaded has a large capacity. The use of optical disk drives is being expanded to an auxiliary memory device for personal computers. Accordingly, the optical disk drive should have a plurality of optical heads corresponding to multiple users, so that they each may process information independent of time with respect to one disk loaded therein.
In the conventional technologies, for example, in a cable television systems, use has been made of a video disk drive which has four optical heads disposed at 90.degree. intervals and provides images through four lines (see Nikkei Electronics Asia, March, 1994, pp30 & 31). However, the four optical heads of the video disk drive operate merely to sequentially read out the same information (or image) at predetermined time intervals but cannot be selectively and freely operated by multiple users. In other words, the purpose of such a video disk drive is to give one user four times the opportunity for viewing the same image.
Therefore, improvements to the above system are being sought, to realize independent operation of the above four optical heads, such that four users each can process desired information (view images) at any time. Also, to accommodate more users, additional optical heads should be installed and the optical heads should be reduced in size accordingly. However, given a 30 cm-diameter disk, the practical limit to the arrangement of ordinary optical heads mandates four such heads at most.